Framing co-production in socio-hydrological modelling for drought impact assessment and mitigation

Drought is an increasingly widespread and impactful disaster across the world, causing serious impacts on health, agriculture, societies and the environment. For its complex nature, assessing the present and future impacts of droughts is a prominent challenge. Droughts can be defined differently according to the sectoral, disciplinary, and socio-economic domains, making drought impact assessment often ill-defined or incomplete. For example, droughts may or may not occur after a period of scarce precipitation, depending on local water access and use. Drought impacts are increasingly understood to be socially-influenced processes instead of mere hydro-climatic events. Transdisciplinary approaches to co-producing drought impact assessments and co-defining drought mitigation strategies are therefore particularly needed, while presenting specific challenges and differences compared to participatory approaches traditionally used for other natural hazards. Drawing from a diverse body of literature on participatory modelling research in the fields of transdisciplinary sustainability science, integrated water resources management, socio-hydrology and hydrosocial studies, we introduce a comprehensive framework for guiding participatory socio-hydrological modelling oriented to problem solving and real case applications. The framework is composed of two parts. The first part sets up a collaborative space by defining 1) a fitting drought governance space, 2)  potential shared definitions of drought impact; while the second part provides a practical guidance on 3) the biophysical as well as perceived features contributing to drought impact, 4) how and in which phase of the workflow to promote a proactive stakeholders involvement and 5) the potential pitfalls and uncertainty analysis to assess the equity and sustainability of the identified solutions. We further illustrate how such a framework can capture the different dimensions of participation throughout the modelling phases in some case studies to elucidate the applicability of the proposed approach in advancing research and action on drought impact assessment and mitigation.